• Journal of Dairy Science and Biotechnology
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• v.22 no.1
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• pp.13-25
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• 2004

High concentration of cholesterol in the blood streams of humans has been recognized as a risk factor in the coronary heart disease. Recently, lactobacilli having high bile salt hydrolase activity have been claimed to decrease the concentration of the blood stream cholesterol in humans. In particular, many studies have been reported on the hypocholesterolemic effect of Lactobacillus acidophilus, a normal component of the microflora of the small intestine. Bile salts are excreted as bile into duodenum in the form of N-acyl compounds conjugated with glyine or taurine. Bile excretion is the major route of eliminating cholesterol from the body as well as one of the important pathways of cholesterol metabolism. Since conjugated bile salts are necessary to emulsify cholesterol, deconjugation of bile salts by lactobacilli could decrease intestinal absorption of cholesterol. Free bile salts as well as cholesterol are less soluble than the conjugated bile salts. Therefore, few free bile salts and cholesterol are absorbed through the enterohepatic circulation and most of them are easily excreted via feces. Thus, serum cholesterol could be removed from the body pool by synthesizing new conjugated bile salts to replace the excreted ones.

• YAKHAK HOEJI
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• v.38 no.1
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• pp.78-85
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• 1994

From phase solubility studies bile acids and bile salts were found to form stable inclusion complexes with ${\beta}-cyclodextrin$ in aqueous solution. Stability constant of bile acids were larger than that of bile salts. Phase solubility diagrams of most bile acids showed Higuchi's $A_I$ type but lithocholic acid showed $B_S$ type. Not only the solubility of bile acids but also that of ${\beta}-cyclodextrin$ increased, especially in cases of cholic acid and ursodeoxycholic acid. Solubility increase of bile acids from their ${\beta}-cyclodextrin$ inclusion complex followed the order : cholic acid>ursodeoxycholic acid>chenodeoxycholic acid>deoxycholic acid>lithocholic acid. It seems that solubility of inclusion complexes was directly related with the hydrophilicity of bile acids.

• Journal of Pharmaceutical Investigation
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• v.22 no.3
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• pp.211-217
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• 1992

Stabilization of liposomes against degradation by bile salts has been investigated in order to develop a liposomal model system for oral drug delivery. Two polysaccharides, amylopectin (AP) and chitin (CT), were employed to coat both empty liposomes and bromthymol blue (BTB)-encapsulated liposomes by adsorption-coating techniques. Turbidity changes and BTB-release characteristics in pH 5.6 buffer solutions with or without bile salts, sodium cholate and sodium glycocholate, were observed to compare the differences between uncoated liposomes and polysaccharide-coated liposomes. Initial turbidities of both uncoated and polysaccharide-coated liposomes in buffer solution were kept constant within 3% range during 4 hours of experiments. But they were decreased in a different manner in bile salts-containing buffer solutions, showing 10% or less decrease for polysaccharide-coated liposomes and 25% or more decrease for uncoated liposomes. BTB release from uncoated liposomes has been greatly increased upto 90% after 4 hours in bile salts-containing buffer solution, which is a clue for breakdown of liposomal vesicles. However, polysaccharide-coated liposomes showed the controlled-release pattern which is proportional to square-root of time, followed by around 50% release for the same time period. Consequently, it is possible to conclude that these polysaccharide-coated liposomes might be an available system for oral delivery of a drug which is unstable in gut environment.

• Asian-Australasian Journal of Animal Sciences
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• v.18 no.2
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• pp.282-295
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• 2005

The processing of dietary lipids can be distinguished in several sequential steps, including their emulsification, hydrolysis and micellization, before they are absorbed by the enterocytes. Emulsification of lipids starts in the stomach and is mediated by physical forces and favoured by the partial lipolysis of the dietary lipids due to the activity of gastric lipase. The process of lipid digestion continues in the duodenum where pancreatic triacylglycerol lipase (PTL) releases 50 to 70% of dietary fatty acids. Bile salts at low concentrations stimulate PTL activity, but higher concentrations inhibit PTL activity. Pancreatic triacylglycerol lipase activity is regulated by colipase, that interacts with bile salts and PTL and can release bile salt mediated PTL inhibition. Without colipase, PTL is unable to hydrolyse fatty acids from dietary triacylglycerols, resulting in fat malabsorption with severe consequences on bioavailability of dietary lipids and fat-soluble vitamins. Furthermore, carboxyl ester lipase, a pancreatic enzyme that is bile salt-stimulated and displays wide substrate reactivities, is involved in lipid digestion. The products of lipolysis are removed from the water-oil interface by incorporation into mixed micelles that are formed spontaneously by the interaction of bile salts. Monoacylglycerols and phospholipids enhance the ability of bile salts to form mixed micelles. Formation of mixed micelles is necessary to move the non-polar lipids across the unstirred water layer adjacent to the mucosal cells, thereby facilitating absorption.

• Proceedings of the Korean Society of Toxicology Conference
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• 2002.11b
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• pp.107-114
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• 2002

Cholestatic liver injury results from the accumulation of toxic bile salts within the liver. The aim of the present study was to understand the mechanism of bile salts-induced hepatocellular apoptosis in bile duct-ligated (BDL) rats, using Western blot and immunohistochemical analysis.(omitted)

• Journal of Microbiology and Biotechnology
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• v.22 no.10
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• pp.1432-1440
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• 2012

Weissella confusa 31, an isolate from human feces, possesses desirable properties as a probiotic strain, including bile salt resistance. W. confusa 31 is not inhibited by bile salts up to 0.3% concentration. Proteins affected by bile salts (0.05%) were examined by 2-D gel electrophoresis. Our proteomic analyses revealed that the intensities of 29 spots were changed, where 17 increased (including 2 spots observed only under the bile salts stress conditions) and 12 decreased. Proteins were identified by MALDI-TOF mass spectrometry. Proteins increased in the band intensities included adenylate kinase (12.75-fold increase), Clp-like ATP-dependent protease (11.91-fold), 6-phosphogluconate dehydrogenase (10.35-fold), and HSP 70 (5.07-fold). Some of the increased or decreased proteins are also known to be involved in other types of stress responses.

• Korean Journal of Veterinary Research
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• v.37 no.4
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• pp.745-754
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• 1997

This study was designed to investigate the effects of cholate and deoxycholate on pancreatic exocrine secretion in conscious sheep with external bile and pancreatic fistulae. Bile and pancreatic juices were collected for a basal period of 2 hours. The pancreatic juice was returned to the intestine. Bile salts were infused into the jugular vein or duodenum for 90 minutes at the rate of 0.7mg/kg/min. Cholate and deoxycholate significantly increased the flow rate, pH and bicarbonate concentration of bile juice, but decreased the flow rate of pancreatic juice. The effects induced by intraduodenal infusion of both bile salts were significantly greater than those by intravenous infusion. Protein concentration and amylase activity in pancreatic juice were also significantly decreased by both bile salts; the effects were greater when the bile salts were infused into the duodenum than into the vein. The inhibitory effects induced by deoxycholate infusion were significantly greater than those by cholate infusion. The plasma concentration of secretin was significantly increased by intravenous infusion of deoxycholate, but it was not effected by intraduodenal infusion of both bile salts. The results indicated that cholate and deoxycholate markedly increased the secretion of bile juice and decreased the pancreatic exocrine secretion, although these effects were variable depending on the chemical composition or infusion routes.

• Journal of Pharmaceutical Investigation
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• v.39 no.2
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• pp.97-106
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• 2009

Although lovastatin (LS) is widely used in the treatment of hypercholesterolemia, its bioavailability is known to be around 5%. This study was aimed to increase the solubility and dissolution-permeation rates of LS using solid dispersions (SDs) with bile salts. The solubilities of LS in water, aqueous bile salt solutions and non-aqueous vehicles were determined, and effects of bile salts on the cellulose or duodenal permeation of LS from SDs were evaluated using a horizontal permeation system. SDs were prepared at various ratios of LS to carriers, such as sodium deoxycholate (SDC), sodium glycocholate (SGC) and/or 2-hydroxypropyl-$\beta$-cyclodextrin (HPCD). The addition of bile salts (25 mM) in water increased markedly the solubility of LS by the micellar solubilization. Some non-aqueous vehicles were effective in solubilizing LS. From differential scanning calorimetric studies, it was found that the crystallinity of LS in SDs disappeared, indicating a formation of amorphous state. The SDs showed markedly enhanced dissolution compared with those of their physical mixtures (PMs) and drug alone. In the dissolution-permeation studies using a cellulose membrane, the donor and receptor solutions were maintained as a sink condition using pH 7.0 phosphate buffer containing 0.05% sodium lauryl sulfate (SLS). The flux of LS alone was nearly same as that of LS-SDC-HPCD (1:3:6) PM. However, the flux of LS-SDC-HPCD (1:3:6) SD slightly increased compared with drug alone and PM, suggesting that entrapment of LS in micelles does not significantly hinder the permeation across cellulose membrane. In the dissolution-duodenal permeation studies using a LS-HPCD-SDC (1:3:6) SD, the addition of various bile salts in donor solutions (25 mM) enhanced the permeation of LS markedly, and the fluxes were found to be $0.69{\pm}0.41$, $0.87{\pm}0.51$, $0.84{\pm}0.46$, $0.47{\pm}0.17$ and $0.68{\pm}0.32{\mu}g/cm^2/hr$ for sodium cholate (SC), SDC, SGC, sodium taurodeoxycholate (STDC) and sodium taurocholate (STC), respectively. The stepwise increase of donor SGC concentration increased the flux dose-dependently. From the relationship of donor SGC concentration and flux, the concentration of SGC initiating the permeation across the duodenal mucosa was calculated to be 11.1 mM, which is nearly same as the critical micelle concentration (CMC, 11.6 mM) of SGC. However, with no addition of bile salts and below CMC, the permeation was very limited and irratic, indicating that LS itself is very poor permeable. Higher protions of bile salt in SD such as LS-SDC or LS-SGC (1 : 49 and 1 : 69) showed highly promoted fluxes. In conclusion, SD systems with bile salts, which may form their micelles in intestinal fluids, might be a promising means for providing enhanced dissolution and intestinal permeation of practically insoluble and non-absorbable LS.

• Journal of Microbiology and Biotechnology
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• v.21 no.8
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• pp.838-845
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• 2011

The present work describes the identification, purification, and characterization of bile salt hydrolase (BSH) from Bifidobacterium animalis subsp. lactis. The enzyme was purified to electrophoretic homogeneity by hydrophobic chromatography, ion-exchange chromatography and ultrafiltration. SDS-PAGE analysis of putative BSH and gel filtration revealed that the analyzed protein is presumably a tetramer composed of four monomers each of about 35 kDa. The purified enzyme was analyzed by liquid chromatography coupled to LTQ FT ICR mass spectrometry and unambiguously identified as a bile salt hydrolase from B. animalis. The isoelectric point of the studied protein was estimated to be around pH 4.9. The pH optimum of the purified BSH is between 4.7 to 6.5, and the temperature optimum is around 50oC. The BSH of B. animalis could deconjugate all tested bile salts, with clear preference for glycine-conjugated bile salts over taurine-conjugated forms. Genetic analysis of the bsh showed high similarity to the previously sequenced bsh gene from B. animalis and confirmed the usefulness of bile salt hydrolase as a genetic marker for B. animalis identification.

• Food Science of Animal Resources
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• v.24 no.2
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• pp.164-170
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• 2004

The purpose of this study is to isolate probiotic lactic acid bacteria (LAB) that produced bile salts hydrolase. One hundred twenty strains were initially isolated from human feces. Based on their resistance of acid, tolerances of bile salts, and inhibitory activity against Escherichia coli, five strains were selected. A strain producing highest activity of bile salts hydrolase was identified as Lactoacillus plantarum using API carbohydrate fermentation pattern and 16S rRNA sequences, and named CK102. Lactobacillus plantarum CK102 survived at a level of 1.36${\times}$10$\^$8/ CFU/$m\ell$ in pH 2 buffer for 6 h and showed exhibited excellent bile tolerance. When L plantarum CK102 was cultured with E. coli in MRS broth, no viable cells of E. coli was detected after 18 h fermentation. These results suggest that Lactobacillus plantarum CK 102 may be commercially used for the probiotic culture.